This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Viruses are the cause of many human diseases through out the world, and result in major financial losses to society. In the United States Influenza, a human pathogen, is responsible for an estimated total direct and indirect cost of $10 billion per year, and the costs of a serious future pandemic could cost hundreds of billions of dollars. Investigating virus assembly and entry will help researchers develop novel anti-viral targets and vaccines. The focus of this proposal is to use to electron microscope tomography to answer key questions about RNA virus lifecycle in vivo.